1. Field of the Invention
The present invention relates to fabrics for use in paper machines, and, more particularly, to fabrics used for moulding fiber webs.
2. Description of the Related Art
A paper machine typically includes a number of discrete sections along the running length of the machine, such as the fordrinier section, forming section, press section, and drying section. Each section of the paper machine typically includes a plurality of rolls and possibly other components which carry a corresponding fabric. A fabric typically has opposite ends which are joined together to define an endless fabric carried by the rolls, with the particular configuration of the fabric corresponding to the particular use in the paper machine.
One type of fabric is a through air dryer (TAD) fabric used to produce a tissue web. During production of such a tissue web using the TAD drying process, the tissue web is moulded inside the fabric structure, creating pillows that provide desired bulk and water absorption properties to the tissue web. At the end of the TAD process, the tissue web is removed from the fabric topography to be transported downstream in the machine direction (MD) of the paper machine. It is therefore desirable for the fabric to have good sheet release properties so that the tissue web can be successfully removed from the TAD fabric. The release properties of the fabric can be affected by the shape of the individual filaments in the fabric and chemical release agents applied to the fabric. The use of chemical release agents is minimized so as not to adversely affect the runability and production cost issues.
What is needed in the art is a fabric for TAD applications having better release properties than conventional fabrics.